EXHIBIT NO. 21 21. SUBSIDIARIES (all wholly-owned, except where otherwise indicated) ------------ State of Name Incorporation ---- ------------- Aalert Paging Company Delaware Subsidiaries of Aalert Paging Company: Aalert Paging Company of Phoenix Delaware Aalert Paging Company of Sacramento California Aalert Paging Company of Salt Lake City Delaware Aalert Paging Company of San Diego California Aalert Paging Company of San Francisco California Aalert Paging Company of Tucson Delaware Blue Mountain Consolidated Water Company Pennsylvania Citizens Cable Company Delaware Citizens Communications Services, Inc. California Citizens Mohave Cellular Company Delaware Citizens Resources Company Delaware Citizens Telecommunications Company Delaware Citizens Telecommunications Company of California California Citizens Telecommunications Company of Idaho Delaware Citizens Telecommunications Company of Montana Delaware Citizens Telecommunications Company of New York New York Citizens Telecommunications Company of Oregon Delaware Citizens Telecommunications Company of Utah Delaware Citizens Utilities Company of California California Citizens Utilities Company of Illinois Illinois Subsidiaries of Citizens Utilities Company of Illinois: Derby Meadows Utility Company, Inc. Illinois DuPage Utility Company Illinois Citizens Utilities Company of Ohio Ohio Citizens Utilities Company of Pennsylvania Pennsylvania Citizens Utilities Home Water Company Pennsylvania Citizens Utilities Rural Company, Inc. Delaware Citizens Utilities Water Company of Pennsylvania Pennsylvania CU CapitalCorp Delaware Subsidiary of CU CapitalCorp: Electric Lightwave, Inc./(1)/ Delaware Electric Energy Export Corporation Arizona Flowing Wells, Inc. Indiana Francis Land and Water Company California Glen Alsace Water Company Pennsylvania Havasu Water Company, Inc. Arizona Jackson Water Works, Inc. California Lake Heritage Utilities, Inc. Pennsylvania Larkfield Water Company California LGS Concord Corporation Minnesota LGS Natural Gas Company Louisiana LGS Securities, Inc. Louisiana Southwestern Capital Corporation Delaware Southwestern Investments, Inc. Nevada Sun City Sewer Company Arizona Sun City Water Company Arizona Sun City West Utilities Company Arizona Tubac Valley Water Company, Inc. Arizona Utilities Advances Corporation New York Valley Utility Company Ohio /(1)/ 97% voting stock ownership